The engine we hear in reply #10, doesn't sound bad at all, be it that rpm seems a bit low. Verify your tach is accurate or doublecheck with a digital one*. I've once worked on a CB550K3 that showed 1400 rpm on its ND tacho, that actually was a true 1000.
The engine idles too high in the vid in #11. You may find this thread worth reading. It is about an error on p.8 in the Shop Manual Honda CB500-550.
http://forums.sohc4.net/index.php/topic,184299.msg2133957.html#msg2133957 You may find the complete thread interesting.
I have no experience with other than stock airfilters, jets and exhausts**. I sincerely hope someone will soon be able to reproduce airfilter cases by 3D printing.
Where exactly does that carb leak fuel? Does fuel exit at its orifice or where the tube sits in the carb body? BTW, the airscrew of that carb looks to be screwed in quite deep. Could it be you accidently interpret 'a turn' as 180
o where 360
o is the norm?
*When I bought my automotive multimeter, they were a fortune. Nowadays you can find them for a reasonable price, hence my advice: if you need to buy a multimeter,
if, then make it an automotive one. But you may also try to score a vintage tach/dwell tester. A dampened analogue indicator is so much nicer to work with than nervous ever changing digits. Downside: the latter is too big to have with you
en route.
** I remember back in the day (in Europe) all aftermarket 4 in ones advertised with: no rejetting required. The only exception that I remember, was a special racing model by Sebring.
